(1) Field of the Invention
This invention relates generally to the field of pallet assembly devices and methods of assembling pallets. More particularly, the invention pertains to an automated pallet assembly apparatus for producing block-style pallets that is configured to automatically attach three blocks to an individual slat in a manner to form a stringer of a block-style pallet. The apparatus is configured to automatically repeat the procedure utilizing blocks and slats automatically retrieved from stacks of blocks and slats held in dispensing stations of the apparatus. The assembly apparatus provides an economical method for rapidly fabricating block-style pallet stringers.
(2) Related Art
Numerous automated devices have been developed to facilitate the assembly of pallets. These devices include relatively inexpensive devices that perform only small sub-portion of pallet assembly and also include large scale pallet assembly devices that are capable of automatically producing several hundred pallets per hour.
Despite the many developments made in industry for assembling pallets, the are many disadvantages associated with various types of prior art automated pallet assembly devices. One obvious such disadvantage is the cost of such assembly devices, which can make large automated assembly devices uneconomical for production facilities that do not have the demand for operating such devices continually. Other less complex and less expensive assembly devices require slats, stringers, blocks, or other pallet components to be manually positioned in their relative assembled positions or within jigs or carriages. Such manual positioning tends to increase labor costs and/or slow production rates. At least some relatively small scale assembly devices, such as the device disclosed in U.S. Pat. No. 4,403,388, automatically position at least some pallet components in their assembled position prior to assembling such components. However, such devices, despite being relatively small in scale, often have numerous moving parts that are subject to wearing and/or require frequent maintenance.
It is in view of the above problems that the present invention was developed. The present invention overcomes many of the disadvantages associated with prior art pallet assembly devices by providing a pallet assembly device for, and method of, automatically positioning various pallet components, as well as automatically attaching such components together, without requiring numerous moving parts.
One aspect of the invention generally pertains to pallet assembly device that preferably comprises a slat dispensing station, a block dispensing station, a clamping station, a slat conveying mechanism, a block conveying mechanism, and an automatic fastening device. The slat dispensing station is configured and adapted to hold a plurality of pallet slats stacked vertically one above another. Likewise, the block dispensing station is configured and adapted to hold a plurality of pallet blocks stacked vertically one above another. The clamping station is configured and adapted to bias a block into engagement with a slat. The slat conveying mechanism operatively connects the slat dispensing station to the clamping station and is configured and adapted to repetitively engage and separate a lower most slat from a plurality of slats positioned in the slat dispensing station and to transfer such a slat to the clamping station. The slat conveying mechanism is further configured and adapted to position that slat at first, second, and third distinct stopped positions relative to the clamping station. The block conveying mechanism is configured and adapted to repetitively engage and separate a lower most block from a plurality of blocks positioned in the block dispensing station and to transfer that block to the clamping station. The block conveying mechanism is further configured and adapted to position blocks above the slat when the slat is stopped in any one of the first, second, and third distinct stopped positions. The automatic fastening device is configured and adapted to force a fastener upwardly through the slat and into a block when the slat and has been stopped in any one of the first, second, and third positions and such a block is being bias into engagement with the slat.
Another aspect of the invention generally pertains to pallet assembly device that preferably comprises a component dispensing station, a clamping station, and a component conveying mechanism. The component dispensing station is configured and adapted to hold a plurality of pallet components and the clamping station is configured and adapted to bias pallet components together. The component conveying mechanism operatively connects the component dispensing station to the clamping station and comprises a plurality of wheels that are mounted to the assembly device for rotation about separate axes. The wheels are positioned to simultaneously engage opposite sides of a pallet component when such a component is being transferred by the component conveying mechanism to the clamping station. The component conveying mechanism also comprises a drive motor that is operatively connected to at least one of the plurality of wheels in a manner allowing the drive motor to rotationally drive and rotationally stop at least one of the plurality of wheels to thereby adjust the position of a pallet component relative to the clamping station.
Yet another aspect of the invention pertains to a method of assembling a pallet that preferably comprises the step of providing an automated pallet assembly apparatus having an assembly path, a slat dispensing station, and a block dispensing station, with the assembly path operatively connecting the slat dispensing station to the block dispensing station. The method further preferably comprises providing a plurality of slats to the slat dispensing station and providing a plurality of blocks to the block dispensing station.
The method also preferably comprises utilizing the assembly apparatus to automatically move a first one of the plurality of slats longitudinally along the assembly path from the slat dispensing station toward the block dispensing station and to automatically stop the movement of the first slat at a first position along the assembly path. In the first position, a first longitudinal end of the first slat is positioned adjacent the block dispensing station along the assembly path. The method yet further preferably comprises automatically biasing a first block of the plurality of blocks into engagement with the first slat, when it is stopped in the first position, and automatically fastening the first slat to the first block while the first slat and the first block are being biased into engagement with each other.
Still further, the method preferably comprises utilizing the assembly apparatus to automatically longitudinally move the first slat from the first position and to automatically stop the movement of the first slat at a second position along the assembly path. The second position is further along the assembly path from the slat dispensing station than the first position and the method preferably further comprises automatically biasing a second block into engagement with the first slat, when it is in the second position, and automatically fastening the first slat to the second block while the first slat and the second block are being biased into engagement with each other.
Yet further, the method preferably comprises utilizing the assembly apparatus to automatically longitudinally move the first slat from the second position and to automatically stop the movement of the first slat at a third position along the assembly path. In the third position, the longitudinal end of the slat opposite its first longitudinal end is positioned adjacent the block dispensing station along the assembly path. Finally, the method yet further preferably comprises automatically biasing a third block into engagement with the first slat, when it is in the third position, and automatically fastening the first slat to the third block while the first slat and the third block are being biased into engagement with each other.
Further features and advantages of the present invention, as well as the structure and operation of an embodiment of the present invention, are described in detail below with reference to the accompanying drawings.